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Homes Are Flooding Outside FEMA’s 100-Year Flood Zones, Exposing Racial Inequality

Homes Are Flooding Outside FEMA’s 100-Year Flood Zones, Exposing Racial Inequality
People walk down a flooded street as they evacuate their homes after the area was inundated with flooding from Hurricane Harvey on August 27, 2017 in Houston, Texas. Joe Raedle / Getty Images

Kevin T. Smiley

When hurricanes and other extreme storms unleash downpours like Tropical Storm Beta has been doing in the South, the floodwater doesn't always stay within the government's flood risk zones.

New research suggests that nearly twice as many properties are at risk from a 100-year flood today than the Federal Emergency Management Agency's flood maps indicate.

Unfortunately, many of the people living in those properties have no idea that their homes are at risk until the floodwaters rise.

I am a sociologist who works on disaster vulnerability. In a new study, I looked at the makeup of communities in Houston that aren't in the 100-year flood zone, but that still flood. What I found tells a story of racial disparities in the city. Research in other cities has shown similar flooding problems in predominantly Black and Hispanic neighborhoods.

Poor stormwater infrastructure, expanding urbanization and limited flood mitigation efforts are a few of the reasons why.

Flooding Outside the Zones

About 15 million Americans live in FEMA's current 100-year flood zones. The designation warns them that their properties face a 1% risk of flooding in any given year. They must obtain flood insurance if they want a federally ensured loan – insurance that helps them recover from flooding.

In Greater Houston, however, 47% of claims made to FEMA across three decades before Hurricane Harvey were outside of the 100-year flood zones. Harris County, recognizing that FEMA flood maps don't capture the full risk, now recommends that every household in Houston and the rest of the county have flood insurance.

New risk models point to a similar conclusion: Flood risk in these areas outstrips expectations in the current FEMA flood maps.

One of those models, from the First Street Foundation, estimates that the number of properties at risk in a 100-year storm is 1.7 times higher than the FEMA maps suggest. Other researchers find an even higher margin, with 2.6 to 3.1 times more people exposed to serious flooding in a 100-year storm than FEMA estimates.

What FEMA’s Flood Maps Miss

Understanding why areas outside the 100-year flood zones are flooding more often than the FEMA maps suggest involves larger social and environmental issues. Three reasons stand out.

First, some places rely on relatively old FEMA maps that don't account for recent urbanization.

Urbanization matters because impervious surfaces – think pavement and buildings – are not effective sponges like natural landscapes can be. Moreover, the process for updating floodplain maps is locally variable and can take years to complete. Famously, New York City was updating its maps when Hurricane Sandy hit in 2012 but hadn't finished, meaning flood maps in effect were from 1983. FEMA is required to assess whether updates are needed every five years, but the majority of maps are older.

Second, binary thinking can lead people to an underaccounting of risk, and that can mean communities fail to take steps that could protect a neighborhood from flooding. The logic goes: if I'm not in the 100-year floodplain, then I'm not at risk. Risk perception research backs this up. FEMA-delineated flood zones are the major factor shaping flood mitigation behaviors.

Third, the era of climate change scuttles conventional assumptions.

As the planet warms, extreme storms are becoming more common and severe. If greenhouse gas emissions continue to increase at a high rate, computer models suggest that the chances of a severe storm dropping 20 inches of rain on Texas in any given year will increase from about 1% at the end of the last century to 18% at the end of this one, a chance of once every 5.5 years. So far, FEMA hasn't taken into account the impact climate change is having on extreme weather and sea level rise.

Racial Disparities in Flooding Outside the Zones

So, who is at risk?

Years of research and evidence from storms have highlighted social inequalities in areas with a high risk of flooding. But most local governments have less understanding of the social and demographic composition of communities that experience flood impacts outside of flood zones.

In analyzing the damage from Hurricane Harvey in the Houston area, I found that Black and Hispanic residents disproportionately experienced flooding in areas beyond FEMA's 100-year flood zones.

With the majority of flooding from Hurricane Harvey occurring outside of 100-year flood zones, this meant that the overall impact of Harvey was racially unequal too.

Research into where flooding occurs in Baltimore, Chicago and Phoenix points to some of the potential causes. In Baltimore and Chicago, for example, aging storm and sewer infrastructure, poor construction and insufficient efforts to mitigate flooding are part of the flooding problem in some predominantly Black neighborhoods.

What Can Be Done About It

Better accounting for those three reasons could substantively improve risk assessments and help cities prioritize infrastructure improvements and flood mitigation projects in these at-risk neighborhoods.

For example, First Street Foundation's risk maps account for climate change and present ratings on a scale from 1 to 10. FEMA, which works with communities to update flood maps, is exploring rating systems. And the National Academies of Sciences, Engineering and Medicine recently called for a new generation of flood maps that takes climate change into account.

Including recent urbanization in those assessments will matter too, especially in fast-growing cities like Houston, where 386 new square miles of impervious surfaces were created in the last 20 years. That's greater than the land area of New York City. New construction in one area can also impact older neighborhoods downhill during a flood, as some Houston communities discovered in Hurricane Harvey.

Improving risk assessments is needed not just to better prepare communities for major flood events, but also to prevent racial inequalities – in housing and beyond – from growing after the unequal impacts of disasters.

Kevin T. Smiley is an Assistant Professor of Sociology, Louisiana State University.

Disclosure statement: Kevin T. Smiley receives funding from an Early-Career Fellowship from Gulf Research Program of the National Academies of Sciences, Engineering, and Medicine, and is supported as a Fellow in the Enabling Program for the Next Generation of Hazards and Disasters Researchers as part of the National Science Foundation's Humans, Disasters, and the Built Environment program.

Reposted with permission from The Conversation.

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The world-famous wildlife broadcaster and his royal sidekick appear to have played an active role in the prize's inception, and media coverage has focused largely on them as the faces of the campaign.

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With more and more global attention on the climate crisis, celebrity endorsement of environmental causes has become more common. But why do environmental causes recruit famous faces for their campaigns? And what difference can it make?

'Count Me In'

"We need celebrities to reach those people who we cannot reach ourselves," says Sarah Marchildon from the United Nations Climate Change secretariat (UNFCCC) in Bonn, Germany.

Marchildon is a proponent of the use of celebrities to raise awareness of environmental causes. In addition to promoting a selection of climate ambassadors who represent the UN on sustainability issues, Marchildon's team has produced videos with well-known narrators from the entertainment world: among them, Morgan Freeman and Mark Ruffalo.

"We choose celebrities who have a lifestyle where they are already talking about these issues," Marchildon explains.

"Sometimes they reach out to us themselves, as David Attenborough did recently. And then they can promote the videos on their own social channels which reach more people than we do — for example, if they have 20 million followers and we have 750,000."

Environmental groups focused on their own domestic markets are also taking this approach. One Germany-based organization that uses celebrities in campaigns is the German Zero NGO. Set up in 2019, it advocates for a climate-neutral Germany by 2035.

German Zero produced a video in March 2020 introducing the campaign with "66 celebrities" that supported the campaign, among them Deutschland 83 actor Jonas Nay and former professional footballer Andre Schürrle. They solicit support as well as financial contributions from viewers.

"Count me in," they say, pointing toward the camera. "You too?"

"We are incredibly grateful for the VIPs in our videos," says German Zero spokeswoman Eva-Maria McCormack.

Assessing Success Is Complex

But quantifying the effectiveness of celebrity endorsement of campaigns is not a straightforward process.

"In order to measure effectiveness, first of all you need to define what is meant by success," says Alegria Olmedo, a researcher at the Zoology Department at the University of Oxford.

Olmedo is the author of a study looking at a range of campaigns concerning pangolin consumption, fronted by local and Western celebrities, in Vietnam and China. But she says her biggest stumbling block was knowing how to measure a campaign's success.

"You need a clear theory of change," explains Olmedo. "Have the celebrities actually helped in achieving the campaign's goals? And how do you quantify these goals? Maybe it is increased donations or higher engagement with a cause."

A popular campaign in China in recent years saw famous chefs Zhao Danian and Shu Yi pledge to abstain from cooking endangered wildlife. While the pledge achieved widespread recognition, both Olmedo and Marchildon say it's difficult to know whether it made any difference to people's actions.

"In life we see a thousand messages every day, and it is very hard to pinpoint whether one campaign has actually made a difference in people's behavior," she explains.

Awareness Is Not Enough

Many campaigns that feature celebrities focus on raising awareness rather than on concrete action — which, for researcher Olmedo, raises a further problem in identifying effectiveness.

"Reach should never be a success outcome," she says. "Many campaigns say they reached a certain number of people on social media. But there has been a lot of research that shows that simply giving people information does not mean they are actually going to remember it or act upon it."

But anecdotal evidence from campaigns may suggest reach can make an active difference.

"Our VIP video is by far the most watched on our social media channels," McCormack from German Zero says. "People respond to it very directly. A lot of volunteers of all ages heard about us through that video."

However, some marketing studies have shown that celebrity endorsement of a cause or product can distract from the issue itself, as people only remember the person, not the content of what they were saying.

Choosing the Right Celebrity

Celebrity choice is also very important. Campaigns that use famous faces are often aiming to appeal to members of the public who do not necessarily follow green issues.

For certain campaigns with clear target audiences, choosing a climate scientist or well-known environmentalist rather than a celebrity could be more appealing — Attenborough is a classic example. For others, images and videos involving cute animals may be more likely to get a message heard than attaching a famous face.

"We choose celebrities who have a lifestyle where they are already talking about these issues," says Marchildon from the UN. "You need figures with credibility."

McCormack cites the example of Katharine Hayhoe, an environmental scientist who is also an evangelical Christian. In the southern United States, Hayhoe has become a celebrity in her own right, appealing to an audience that might not normally be interested in the messages of climate scientists.

But as soon as you get a celebrity involved, campaigns also put themselves at risk of the whims of that celebrity. Prince William and younger members of the royal family have come under fire in recent years for alleged hypocrisy for their backing of environmental campaigns while simultaneously using private jets to fly around the world.

But Does It Really Work?

While environmental campaigns hope that endorsement from well-known figures can boost a campaign, there is little research to back this up.

"The biggest finding [from my study] was that we were unable to produce any evidence that shows that celebrity endorsement of environmental causes makes any difference," says Olmedo.

This will come as a blow to many campaigns that have invested time and effort into relationships with celebrity ambassadors. But for many, the personal message that many celebrities offer in videos like that produced by German Zero and campaigns like the Earthshot Prize are what counts.

The research may not prove this conclusively — but if the public believes a person they respect deeply personally cares about an important issue, they are perhaps more likely to care too.

"I personally believe in the power this can have," says Marchildon. "And if having a celebrity involved can get a single 16-year-old future leader thinking about environmentalist issues — that is enough."

Reposted with permission from DW.

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